1. Field of the Invention
The present invention relates to a sheet supplying apparatus for automatically supplying sheets one by one.
2. Related Background Art
In recording apparatuses such as printers, copying machines, facsimile machines and the like, an image of a dot pattern is recorded on a recording sheet such as a paper sheet, a plastic film and the like by selectively energizing energy generating elements of a recording head in response to inputted image information. Such recording apparatuses can be grouped into an ink jet type, a wire dot type, a thermal type, an electrophotographic type and the like in accordance with the recording fashion. Further, the recording sheet used with the recording apparatus may be a thick sheet such as a post card, an envelope or the like, or a special sheet such as a plastic film, as well as a normal sheet. The recording sheets can be supplied one by one by a manual insertion or can be supplied automatically and continuously by an automatic sheet supplying apparatus.
FIG. 52 is a perspective view showing an example of a conventional sheet supplying apparatus. As shown in FIG. 52, such sheet supplying apparatus generally has a sheet supply drive portion comprising left (L) and right (R) sheet supply rollers 1101, 1102, a sheet supply roller shaft 1106, a drive gear 1107 and the like, and a sheet supply cassette portion comprising left (L) and right (R) side guides 1103, 1104, a pressure plate 1105 and the like and on which sheets are loaded. A driving force from a recording sheet feeding apparatus of the recording apparatus is transmitted to the drive gear 1107 to rotate the sheet supply rollers 1101, 1102, thereby separating sheets one by one via the left (L) and right (R) separation claws 1109, 1110 and supplying a separated sheet P.
However, in this conventional sheet supplying apparatus, since the pair of left and right sheet supply rollers 1101, 1102 and the pair of left and right separation claws (separation means) 1109, 1110 are provided, the following disadvantages occur.
(1) The apparatus is made complicated and expensive because of numerous of parts. PA1 (2) The apparatus is made large-sized since a space through which the sheet supply roller shaft 1106 passes is required.
To eliminate such disadvantages, as disclosed in U.S. Pat. No. 4,372,547, a technique wherein a separation claw and a sheet supply roller are arranged at only one side (left or right) of the apparatus has been proposed. However, when the separation claw and the sheet supply roller are arranged at only one side of the apparatus, the sheet is skew-fed during the separation thereof. Therefore, in the above U.S. Pat. No. 4,372,547, a special roller for preventing the skew-feed of the sheet is added, which makes the reduction of cost difficult.